package ch8;

import java.util.Scanner;

public class Example8_9 {
    public static void main (String args[ ]) {
        String regex = "[a-zA-Z|0-9|_]+";
        Scanner scanner = new Scanner(System.in);
        String str = scanner.nextLine();
        if(str.matches(regex)) {
            System.out.println(str+"是英文字母,数字或下划线构成");
        }
        else {
            System.out.println(str+"中有非法字符");
        }
    }
}
